Automatic battery-charging system



March 2 1926. 1,574,747

C. AUTH AUTOMATIC BATTERY CHARGING SYSTEM i'ied July 19, 1923 vwento'cpatented Mar. 23, 192%.

were srrss CHARLES AU'lI-I, OF NEW YORK, N. Y.,

ASSIGNOR TO EMMA LOUISE AUTH, OF

BRQOKLYN, NEW YORK.

AUTOIvIATIC BATTERY-CHARGING SYSTEM.

Application filed July 19, 1923. Serial No. 652,484.

To (ZZZ whom 2'25 may concern:

Be it known that I, CHARLES Anal-r, a citizen of the United States, anda resident of New York city, in the county of New York and of New York,have invented a certain new and useful Automatic Battery- ChargingSystem, of which the following is a specification.

The invention relates to an electrical system wherein storage batteriesare employed as the source of energy for a service circuit, and whereinthe voltage of the batteries is automatically maintained at the propervalue by charging the batteries from a lighting or other power circuitwhen their voltage falls below a certain point. One ob ject of theinvention is to provide a system of the above nature wherein theconnections made betwcenthe batteries and the power circuit when thebattery is to be charged, will be positively held in closed positionagainst minor voltage fluctuations, to prevent the repeated opening andclosing of such connections when the voltage of the batteries hoversaround the charging point. In other words, once the charging operationbegins, the connections between the power circuit and the batteries areso controlled as to continue charging until a point is reached wherethere is little likelihood that the charging operation will be soonresum d after it ceases.

The invention also comprises certain precautions against abnormalcircuit conditions, particularly by way of opening the service circuitwhen the voltage impressed thereon rises above a predetermined value,all as is more fully set forth hereinafter.

Further objects and advantages of the invention will be in part obviousand in part specifically pointed out in the description hereinaftercontained, which, taken in connection with the accompanying drawings,discloses a preferred embodiment thereof; such embodiment, however, isto be considered merely as illustrative of its principles.

In the drawings:

The single figure is a diagrammatic view of a system adapted to operatein accordance with the invention.

In electrical systems of the above nature, the charging connectionsbetween the power circuit and the batteries are usually made and brokenby means of a relay or the like, which is controlled as to its positionaccording to the voltage of the batteries; thus when this voltage is atapproximately the value at which the position of the relay will beshifted, the system tends to charge for a short time until the voltageof the batteries rises slightly, when the relay will be shifted again-tocut out the power circuit, the above hunting of the relay being likelyto be continued over long periods with undue sparking at the contacts,noise, wear, etc. Furthermore, it is a diiiicult matter to adjust orcontrol the electrical or electro-magnetic characteristics of theelements making up such a system, to avoid the above difficulty.

In accordance with the present invention, the switch member which cutsin and out the power circuit, is locked or held in position to such anextent that it will not vibrate or flutter under minor voltagefluctuations. The invention is illustrated as applied to a system havinga power circuit compris ing conductors 1 and 2, a battery circuit havingconductors 8 and 4;, and a service circuit comprising conductors 5 and6.

When the voltage of the battery circuit 3, 4, falls below apredetermined point, a switch member 7 is actuated to close circuitbetween the conductors 1 and 3, and 2 and l respectively. In the presentinstance the switch member '7 is moved to closed position by a coil 8,which is energized when the battery voltage drops; as shown, a relay 9is shunted across the conductors 3 and a in such manner, that when thevoltage of the batteries drops, armature 10 of the relay, which isconnected by a wire 11 to the conductor 3, will fall into engagementwith a contact 12, which is in circuit with the coil 8, through a wire13. At tne same time,

the coil 8 is connected to the remaining battery conductor 4, preferablyas will be later described in greater detail, with the result that theswitch member '7 is held in closed position so long as armature 10engages contact 12, thus charging the batteries.

However, an increase in the battery voltage which is sufiicient to liftarmature 10 away from contact 12 will not necessarily permit switchmember 7 to fall to open position, due to the fact that a locking deviceis also provided to hold the switch closed. In the present instance,this locking device takes the form of a pivoted latch 14 having ashoulder 15 adapted to underlie the end of switch membc '7 when thelatter is in closed position, and the latch 1 lis normally urged by aspring 16 to catch under the switch member 7 when the latter is closed,and hold it closed.

hen the batteries have been charged suificiently to bring their voltageup to a point such that urther charging is not likely to be necessar Ifor asubstantial period of time, the latch 14 is withdrawn from switchmember 7 and, the armature being also ele ated at this time, the switchmember will dro to open position against the shoulder 15 of latch 1%. Inthe instance the latch Li: is retracted by means of coil 17, which isconnected-by a 18., to a contact 19 a sociated with the armature 10 andengaging the latter when the battery voltage has been brought up to apredetermined point. It switch member 7 be closed at this time, circuitwill be made to coil 17 through conductor 11, armature 10, contact 19,wire l8, coil 17, a wire 20 connected between coil 17 and contact 21,which latter engaged by an arm 22 when the switch me iber 7 is closed,and a wire 23 connecting switch member 7 to conductor l. The latch 1 L,however, will not release switch member 7 in case of minor voltageincreases which may have been sufiicient to separate arma ture 10 fromcont ct 12, but only in case armature 10 has beenelei-ated to engagecontact 19 and energize coil 17 sulticiently to hold the latch 14 inretracted position while switch member 7 falls. Thus rapid vibrations ofswitch member 7 are prevented, and the charging operation when oncebegun,

continues to a point where further charging will not be necessary untilafter a suostantial period of time.

In the present instance the latch let also breaks circuit through coil8, after switch member 7 has been closed; as shown, a wire 52% leadsfrom coil 8 to a contact which engages latch 1% when the latter is inretracted position, and the latch. la is connectedto conductor atthrough wire 26; thus circuit may be made through coil 8 only when thelatch isin retracted position,v and the coil is deenergized as soon asswitch member 7 is closed.

urrent [lows from the batteries through conductors 3 and l to theserriceconductors 5 and 6, the negative conductors l and (5 being grounded inthe present instance through a lead 27. I prefer to arrange the systemso that in the event of aln ioriually high 'voltage inthe serviceci1.'cuit .-the latter as well as the charging circuit will lieautoductors 0 matically opened. in the present instance a relay 28 isshunted across the t5BI"."CO conand 6, and a circuit breaker 20 isinterposed in the service circuit and normally held closed by means of apivoted trip 30. The armature 31 of relay 28 is normally in lowerposition, but in case of excessive voltage in the service circuit thecoil of relay 28 draws up the armature 3 and tilts trip to releaseswitch arm '29 and permit a spring 32 associated with such switch arm tomove the latter to open position. breaking the service circuit. Armature31 is connected to conductor 3 by a wire and the trip 30 is connected toCOll 17 through a wire thus when excessive voltage exists in the servicecircuit, coil 17 is energized through conductors 3, 33, armature C} 1.,trip 30, wires 34: and 1S, coil 17-, wire '20, contact 21, switch arm 22and wire 23; the charging circuit, therefore, will be opened due to theretraction of latch 1% from switch member 7.

The system may also include a signal or alarm to'in'dicate the failureof voltage. in the charging circuit; as shown, relay 35 is shuntedacross power conductors l and 2, whereby an armature of the relay isonly held up; but if the voltage should fail between conductors l and 2the armature 36 drops into engagement with a contact 37, making circuitto a trouble lamp or the like 39 to which current is led by conductors 3and ll lVhile a specific embodiment of the invert tion has beendescribed, it will be obvious tlat many changes may be made thereinwithout departing from its principles, as defined in the followingclaims.

I claim:

1'. A battery charging system comprising a power circuit, a chargingcircuit, a service circuit, a switch member for shifting the powercircuit into and out of connection with the charging circuit, a locl'ingdevice adapted to hold said switch member in closed position againstminor voltage fluctuations in the batte =y circuit, circuit breaker insaid service cir iit, and means for releasing said locking oevice uponthe actuation of said circuit breaker.

The combinatimr set forth in claim 1, wherein said locking device isreleased by an electromagnetic coil. and such circuit breaker includescontaralgs making circuit to said coil when the circuit breakerisopencd.

In testimony that I claim the foregoing, l have hereunto set my handlliis 17th day of July, 1923.

